Operation group for automatically winding up curtains

ABSTRACT

An operation group for curtains with winding roll, including a mechanism ( 1 ), a stop device ( 90 ) and a hub ( 9 ), with the mechanism ( 1 ) aimed at imposing and stabilizing a pre-established pre-loading value for first elastic means ( 2 ), present in the winding roll ( 3 ), with the stop device ( 90 ) being aimed at locking the winding roll ( 3 ) to stabilize the curtain in any unwound position and with the hub ( 9 ) aimed at supporting the roll ( 3 ) at one of its ends. The above operation group (G) includes the mechanism ( 1 ) connected to one end ( 3   a ) of the roll ( 3 ) and the stop device ( 90 ), which is connected to the other end of the roll ( 3 ), so as to define the hub ( 9 ).

BACKGROUND OF THE INVENTION

The invention relates to winding up curtains, to be applied to windows and the like.

DESCRIPTION OF THE PRIOR ART

As it is known, the above mentioned curtains are unwound from a winding roll, with a downward movement, up to a position, in which a desired darkening, partial or total, is reached.

The known devices for stabilizing the curtain in different positions, in which it is arranged, as well as for facilitating its winding up, are connected to the winding roll.

Basically, there are two kinds of curtains, one is automatically wound up and the other is manually wound up.

The first type includes elastic means, which are gradually loaded due to the roll rotation, during the curtain unwinding, and which can supply a reaction force strong enough to wind up the roll automatically, after having suitably released a stop device, situated in the roll.

The stop device is aimed at acting automatically in order to stabilize the curtain when the unwinding action is stopped, after the desired position has been reached.

The second type of curtains includes elastic means analogous to the first type, but calibrated in such a way that the reaction force supplied thereby is a function of the curtain weight, in proportion to the unwound quantity thereof.

In the latter case, the curtain position is substantially auto-stabilized and the above mentioned stop device is not necessary.

However, a pulley is mounted coaxial and integral with the winding roll, and is operated by a chain to wind up and unwind the curtain.

The above mentioned elastic means, present in the first and second type, usually include at least one helical spring, whose ends are fastened respectively, to the winding roll and to a motionless element; consequently, the roll rotation, during the curtain unwinding, determines the spring torsion with the increase of the load, and consequently, of the elastic reaction.

Obviously, the curtain good working depends on the correct reaction of the elastic means, which is calibrated by an initial pre-loading of the elastic means, performed usually by known pre-loading means, situated near the winding roll end.

The stop device of the automatically winding up curtains is connected to the relative pre-loading mechanism, in the same operation group.

The construction of the above mentioned group is complicated and expensive, because in includes many elements having complicated shapes.

Another disadvantage derives from the fact that the dimensions of the group depend on the room inside the winding roll, which is rather limited.

What above results in inevitable complication of the moulds for production of these elements, as well as of their assembly, and consequently in high production costs.

The so obtained group has a limited strength, which increases the breaking risk when the curtain is opened or closed.

Moreover, the group cannot be applied to manually winding up curtains, which do not require the stop device, as specified above.

The construction of curtains of the latter type needs a particular pre-loading mechanism, otherwise, it is necessary to set the group stop device to an inoperative condition.

Obviously, the dimensions of the above mentioned curtains, either of one or of another type, can be very different, according to their application.

Consequently, the diameters of the used winding rolls are different, in accordance with the curtain dimensions, and it is necessary to provide appropriate pre-loading devices.

Actually, it is necessary to produce specific elements in accordance to different production needs, elements which are not interchangeable, although substantially and functionally similar.

This causes a series of well known drawbacks, concerning costs and handling, which is in contrast with modern production criteria and the trend to unify the elements as much as possible.

SUMMARY OF THE INVENTION

The object of the present invention is therefore to avoid the above mentioned functional and productive drawbacks by proposing an original operation group for curtains with a winding roll.

The group, according to the invention, must be highly reliable and very simple to construct as well as to assemble, with respect to the known groups.

For the same reason, the proposed group must be extremely versatile, so as to fulfill various production needs.

Another object of the present invention is to propose a group, which can be easily adapted to be mounted on the winding rolls of different diameters, without changing the parts forming it.

The above mentioned objects are achieved, in accordance with the contents of the claims, by an operation group for wind up curtains unwinding from and winding on a winding roll, the operation group including:

-   a mechanism for imposing and stabilizing a pre-established     pre-loading value for first elastic means, present in said winding     roll; -   a stop device for locking said winding roll and stabilizing said     curtain in any unwound position; and -   a hub for supporting the roll at least at one of its ends; -   said operation group being characterized in that the mechanism is     connected to a first end of said roll and said stop device is     connected to a second end of the roll and forms the hub.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristic features of the invention, which are not evident from what has been said above, will be better explained in the following description of a preferred embodiment of the proposed group, in accordance to the contents of claims and with the help of the enclosed drawing tables, in which:

FIG. 1 is a perspective view of the proposed operation group and the inner means of the winding roll;

FIG. 2 is a perspective exploded view of pre-loading mechanism of the proposed group;

FIG. 3 is a view of the same mechanism of FIG. 2, in assembled configuration;

FIG. 4 is a perspective exploded view of a stop device of the proposed operation group;

FIG. 5 is a view of a first adapter ring to be used in the proposed group;

FIG. 6 is a view of a second adapter ring to be used in the proposed group.

BEST MODES OF CARRYING OUT THE INVENTION

With reference to the above mentioned figures, the reference letter G indicates the proposed operation group, designed to be connected to the winding roll 3 of automatically winding up curtains.

The operation group G includes a mechanism 1, a stop device 90 and a hub 9.

The mechanism 1 is aimed at imposing and stabilizing a predetermined pre-loading value for first elastic means 2, formed by an helical spring situated inside the winding roll 3 and aimed, in known way, at supporting the weight of the curtain unwound from the roll 3, as well as at facilitating the curtain winding up on the roll 3.

In the illustrated, non limiting example the mechanism 1 includes a sleeve 4, a barrel 5, introduced into the sleeve 4, and second elastic means 6, situated between the sleeve and the barrel.

Front side acting clutch means 7, situated between the sleeve and the barrel, are defined by a plurality of spaces 70, regularly spaced apart, made in the sleeve 4, and by complementary claws 71 made in a disc 51 formed by the barrel 5.

The barrel 5 can move axially between two positions P1, P2.

When the barrel 5 is in the position P1, the clutch means 7 are connected and when the barrel is in the position P2, the clutch means are disconnected.

Therefore, in the position P1, the barrel 5 is driven into rotation along with the sleeve 4, while in the position P2 it can freely rotate with respect to the sleeve.

The second elastic means 6 are situated inside the sleeve 4 and act, in axial direction, on a cup 52, likewise formed by the barrel 5, so that the claws 71 and the spaces 70 are mutually engaged in absence of other forces.

Due to the assembling necessities, the barrel 5 is formed by two pieces 5 a, 5 b (FIG. 2), which are connected, e.g. by wrench coupling and screw means 53.

A prismatic shank 50, formed by the piece 5 b, extends externally with respect to the sleeve 4, when the mechanism 1 is assembled (FIG. 3), while an axial hole, not shown, facing the opposite side with respect to the shank 50, is made in the piece 5 a.

The mechanism 1 is to be connected to a end 3 a of the winding roll 3, in such a way that:

-   -   the sleeve 4 is coaxially integral with the end 3 a;     -   the barrel 5 is slidingly keyed, by the axial hole, on a grooved         shaft 8, made in known way inside the winding roll 3 and         motionless with respect to the latter;     -   the barrel 5 is driven into rotation along with the proximal end         2 a of the spring 2 of the winding roll 3, to which the         remaining end is fastened, by a connecting pin 13, attached for         rotation to the roll 3.

In particular, the proximal end 2 a of the spring 2 slides, coupled with the shaft 8, in a way completely known and not shown in detail.

For this purpose, the proximal end 2 a is fastened to a bushing 2 b, which is slidingly coupled with the shaft 8 by suitable grooves and corresponding complementary protrusions made in the shaft 8 and the bushing 2 b.

When the assemblage is finished, it is possible to adjust the value of the first elastic means 2 pre-loading, acting manually or with suitable instruments, on the prismatic shank 50, first to make the barrel 5 slide axially from the position P1 to the position P2, thus disengaging the clutch means 7 and then, to increase or reduce the pre-loading by rotating the barrel 5 with respect to the sleeve 4, in one direction or the other.

The release of the barrel 5 makes it slide axially in the opposite direction, from the position P2 to the position P1, due to the elastic reaction of the second elastic means 6, and consequently the clutch means 7 become engaged.

In case the claws 71 and the spaces 70 are not aligned during the release of the barrel, the barrel 5 is driven, by the first elastic means 2, so as to rotate a bit, just until the claws 71 enter the respective spaces 70.

The angular amplitude of the above-mentioned rotation is very limited, inversely proportional to the number of claws 71 and spaces 70, but anyway it does not affect in noticeably way the imposed pre-loading.

The winding roll—mechanism assembly is aimed at being mounted on support means 10, situated beside thee end 3 a (FIG. 3), so that the shank 50 is coupled with a complementary seat 10 a, made in the support means 10 and that the barrel 5 is brought to the position P2, in which the clutch means 7 are disengaged.

In this way, the roll 3 is free to rotate in one direction, to unwind the curtain, and in the other direction, to wind up the curtain, with the defined pre-loading of the first elastic means 2.

The hub 9 is aimed at being connected to the remaining end of the winding roll 3, to allow the latter to be fastened to corresponding support means, not shown, e.g. like the ones present at the opposite end 3 a.

The above mentioned stop device 90, as it has already been referred to in the introductory statement, acts automatically to stabilize the curtain in the desired position.

The stop device 90 of the operation group G proposed by the present invention is so constructed as to form the hub 9 and is positioned at the end of the winding roll 3 corresponding to the latter, that is the end without the mechanism 1.

According to shown non-limiting example, the stop device 90 includes two cylindrical elements 90 a, 90 b, the first of which is integral with the corresponding roll 3 end, similarly to the sleeve 4, while the second is introduced into the first one, similarly to the barrel 5, and is prevented from rotating by a relative prismatic shank 91 coupled with a seat of the corresponding support means.

Two balls 93, situated between the two elements 90 a, 90 b, are introduced freely into first radial seats 190 a formed by the first element 90 a.

Second radial seats 190 b, of suitable shape, are made in said second element 90 b: the unwinding of the curtain is free, independently from the roll 3 rotation speed.

When the curtain reaches the desired position, the unwinding operation is stopped; by allowing a short going back of the curtain, which is pulled by the first elastic means 2 and tends to wind up, the balls 93 are allowed to engage, due to gravity, with the second seats 190 b, so that the roll 3 becomes locked.

In order to unlock the stop device 90, it is necessary to operate the curtain by unwinding it by another short piece, then to release it suddenly: the sudden roll rotation in the winding up direction, determined by the first elastic means 2, keeps the balls 93 in the first seats 190 a, due to the centrifugal force, so that the curtain can be completely wound up on the roll 3.

Finally, the operation group includes two optional elements to be used in case the dimensions of the winding roll 3 are bigger than the one concerned so far, as belonging to another dimension category.

FIG. 5 shows a first adapter ring 30, which is aimed at being fitted on the sleeve 4; on the opposite side, another identical first adapter ring 30 is fitted onto the first cylindrical element 90 a.

The adaptor ring 30 is made in such a way as to maintain the constraints existing between the roll 3, the sleeve 4 and the element 90 a, with respect to rotation.

FIG. 6 shows a second adaptor ring 300, including two half-rings 300 a to be mounted in a corresponding position of the connecting pin 13. The section is aimed at fastening the connecting pin to the roll 3.

The adaptor ring 300 is made in such a way as to maintain the constraint existing between the roll 3 and the connecting pin 13, with respect to rotation.

The use of the adaptor rings 30, 300 allows to use the same operation group for rolls of different diameters, which is evidently positive for the costs reduction.

The proposed operation group is extremely versatile, due to the fact that the stop device 90 is physically separated from the mechanism 1.

This offers clear advantages for constructive simplicity of the relative components, advantages which result in easy assembly, strength and, last but not least, low production costs.

Another advantage, deriving from the constructive characteristics of the mechanism 1, described in the example, concerns the easiness, with which the pre-loading of the first elastic means 2 can be adjusted, without risking that a clumsy movement can unload them completely.

The safety of the mechanism 1 is well seen when, for any reason, the roll must be disassembled from the supports: actually, as soon as the prismatic shank 50 is removed from the relative seat 10 a, the barrel 5 is brought, by the action of the second elastic means 6, back to the position P1, in which the clutch means 7 are mutually engaged, so that the pre-loading of the first elastic means 2 is kept at the prefixed value.

It should be understood that the foregoing description of the invention is intended merely to be illustrative thereof, and that other embodiments, modifications, and equivalents may be apparent to those skilled in the art without departing from the scope of the claims appended thereto 

1. An operation group for wind up curtains unwinding from and winding on a winding roll, the operation group including: a mechanism (1) for imposing and stabilizing a pre-established pre-loading value for first elastic means (2), present in said winding roll (3); a stop device (90) for locking said winding roll (3) and stabilizing said curtain in any unwound position; and a hub (9) for supporting the roll (3) at least at one of its ends; said operation group (G) being characterized in that the mechanism (1) is connected to a first end (3 a) of said roll (3) and said stop device (90) is connected to a second end of the roll (3) and forms the hub (9).
 2. Operation group, according to claim 1, characterized in that: said mechanism (1) includes a sleeve (4) and a barrel (5), the barrel being introduced into the sleeve with possibility to move axially, against the action of associated elastic means (6), between a first and a second positions (P1,P2); clutch means (7) are situated between the sleeve (4) and the barrel (5) and are mutually engaged when said barrel (5) is in the first position (P1), to link the sleeve (4) to the barrel (5) with respect to rotation, and are disengaged from each other, when said barrel (5) is in the second position (P2) to allow the sleeve and barrel a relative free rotation; said mechanism (1) is associated to said first end (3 a) of the winding roll (3), in such a way that: said sleeve (4) is coaxially fixed to the first end (3 a); said barrel (S) has an axial hole and is slidingly keyed onto a shaft (8) situated inside said winding roll (3) and motionless with respect thereto; a proximal end (2 a) of said first elastic means (2) of the winding roll (3) is linked to said barrel (5) and shaft (8), with respect to rotation; said barrel (5) has, at its outer end, a prismatic shank (50), which is operated to make said barrel (5) slide axially, with consequent disengagement of said clutch means (7) and then, to make said barrel (5) rotate in either one or another direction with respect to said sleeve (4), to increase or decrease the pre-loading of said first elastic means (2); the winding roll—mechanism assembly can be mounted on support means (1), so that said shank (50) is coupled with a complementary seat (boa), made in the support means (10), and the clutch means (7) are disengaged.
 3. Operation group, according to claim 2, characterized in that said clutch means (7) include a plurality of spaces (70), regularly spaced apart and made in a front facing of said sleeve (4), and by complementary claws (71) made in a disc (51) formed by said barrel (5).
 4. Operation group, according to claim 2, characterized in that said elastic means (6) are situated inside said sleeve (4) and are aimed at acting, axially, on a cup (52), formed by said barrel (5).
 5. Operation group, according to claim 3, characterized in that said barrel (5) is formed by two pieces (5 a,5 b), locked to each other when the barrel (5) is mounted in said sleeve (4).
 6. Operation group, according to claim 2, characterized in that said elastic means (6) are situated inside said sleeve (4) and are aimed at acting, axially, on a cup (52), formed by said barrel (5), and in that said barrel (5) is formed by two pieces (5 a,5 b), locked to each other when the barrel (5) is mounted in said sleeve (4).
 7. Operation group, according to claim 1, characterized in that: said stop device (90) is formed by a first cylindrical element (90 a) and a second cylindrical element (90 b); said first cylindrical element is fastened to a corresponding end of said roll (3), while the second cylindrical element is introduced into said first cylindrical element and is connected to outer means, for making it motionless; said cylindrical elements first and second (90 a,90 b) feature first radial seats (190 a) and second radial seats (190 b); relative balls (93) are provided, which remain housed in said first radial seats, during curtain unwinding and winding up, to determine an unlocked condition for the stop device (90), said balls (93) being aimed at engaging with said second radial seats (190 b), when rotation is stopped and a short backward rotation is allowed, to determine a locked condition for the stop device (90), in which the curtain is stabilized in a pre-established position.
 8. Operation group, according to claim 1, characterized in that it includes adaptor rings (30,300), first and second respectively, aimed at allowing the group to be mounted on winding rolls (3) of bigger dimensions.
 9. Operation group, according to claim 8, characterized in that said first adaptor ring (30) is aimed at being keyed onto said sleeve (4) and on said first cylindrical element (90 a), and in that said first adaptor ring (30) is shaped in such a way that all the pre-existing constraints to the rotation between said roll (3) and said sleeve (4) and first cylindrical element (90 a) are maintained.
 10. Operation group, according to claim 8, characterized in that said second adaptor ring (300) is formed by two half-rings (300 a) and is aimed at being mounted in a section (13 a) of a connecting pin (13), in which the latter is to be fixed with respect to said roll (3), and in that said second adaptor ring (300) is shaped in such a way as to maintain said rotation constraint.
 11. Operation group, according to claim 2, characterized in that said proximal end (2 a) of said first elastic means (2) is fastened to a bushing (2 b) in turn slidingly coupled with the shaft (8). 